A metal layer formed on a surface of a polymer article for transmitting electromagnetic signals is typically used in the fields of automobiles, manufacturing computers, communications, etc. Selectively forming the metal layer on the surface of the polymer article is a key step in a process of manufacturing such polymer articles.
For example, to form a metal layer, U.S. Patent Application Publication No. 2004/0241422 A1 discloses a method that adds inorganic compound powders having spinel structures to a polymer matrix. The inorganic compound powder may include an inorganic compound that contains elements such as copper, nickel, cobalt, chromium, iron, etc. The method then activates the inorganic compound power using a ultraviolet laser (with a wavelength of 248 nm, 308 nm, 355 nm, or 532 nm) or an infrared laser (with a wavelength of 1064 nm, or 10600 nm). This U.S. Patent Application Publication No. 2004/0241422 A1 discloses that an oxide having a spinel structure may be reduced into metal simple substances under the impact of the laser, and that chemical deposition of metal may be induced using the metal simple substances as a crystal nucleus to form a metal layer. The realization of such a procedure needs strict process control and high laser energy for reducing the oxide having the spinel structure into metal simple substances so as to induce the metal chemical deposition, which increases the requirements for the equipment and processes.